All-solid-state battery

Abstract

The present invention relates to a pouch for an all-solid-state battery and an all-solid-state battery, and, more specifically, the all-solid-state battery according to the present invention comprises: an electrode assembly comprising a first substrate tab, a second substrate tab, and a unit cell; and a pouch exterior material comprising an accommodation part for accommodating the electrode assembly. The unit cell comprises: a positive electrode layer electrically connected to the first substrate tab; a negative electrode layer electrically connected to the second substrate tab; and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer. A first curved portion, formed where the bottom surface of the accommodation part meets a first side surface, has a first radius of curvature, and a second curved portion, formed where the bottom surface of the accommodation part meets a second side surface, has a second radius of curvature, wherein the second radius of curvature is larger than the first radius of curvature.

Description

All-solid-state battery

[0001] The present invention relates to an all-solid-state battery.

[0002]

[0003] Recently, driven by industrial demands, the development of batteries with high energy density and safety is actively underway. For example, lithium-ion batteries are being commercialized not only in the fields of information and communication devices but also in the automotive sector. In the automotive sector, safety is considered particularly important because it is directly related to human life.

[0004] Recently, all-solid-state batteries have been proposed in which the liquid electrolyte of lithium-ion batteries is replaced with a solid electrolyte. By not using flammable organic dispersion media, all-solid-state batteries can significantly reduce the likelihood of fire or explosion in the event of a short circuit. Therefore, such all-solid-state batteries can possess excellent safety.

[0005]

[0006] The problem that the present invention aims to solve is to provide an all-solid-state battery capable of preventing damage to the electrode assembly caused by the pouch outer material.

[0007] Another problem that the present invention aims to solve is to provide a pouch outer material for an all-solid-state battery that can prevent damage to the electrode assembly.

[0008]

[0009] An all-solid-state battery according to the concept of the present invention may include an electrode assembly comprising a first substrate tab, a second substrate tab, and a unit cell; and a pouch outer material comprising a receiving portion for receiving the electrode assembly. The unit cell may include a positive electrode layer electrically connected to the first substrate tab, a negative electrode layer electrically connected to the second substrate tab, and a solid electrolyte layer between the positive electrode layer and the negative electrode layer. The receiving portion may include a bottom surface on which the electrode assembly is seated, and first, second, third, and fourth sides surrounding the bottom surface. At least a portion of the second side may be adjacent to the second substrate tab. A first curved portion formed where the bottom surface and the first side meet has a first radius of curvature, and a second curved portion formed where the bottom surface and the second side meet has a second radius of curvature, wherein the second radius of curvature may be larger than the first radius of curvature.

[0010] An all-solid-state battery according to another concept of the present invention may include an electrode assembly comprising a first substrate tab and a second substrate tab, wherein the bending stiffness of the second substrate tab is greater than the bending stiffness of the first substrate tab; and a pouch outer material comprising a receiving portion for receiving the electrode assembly. The receiving portion includes a bottom surface on which the electrode assembly is seated and a side wall surrounding the bottom surface, wherein the side wall may include a first buffer area adjacent to the first substrate tab and a second buffer area adjacent to the second substrate tab. A first buffer curved surface formed where the first buffer area meets the bottom surface has a first buffer radius of curvature, and a second buffer curved surface formed where the second buffer area meets the bottom surface has a second buffer radius of curvature, wherein the second buffer radius of curvature may be greater than the first buffer radius of curvature.

[0011] A pouch outer material for an all-solid-state battery according to another concept of the present invention comprises a recessed receiving portion, wherein the receiving portion comprises: a bottom surface on which an electrode assembly is seated and first, second, third, and fourth sides surrounding the bottom surface, and each of the first side and the second side may extend in a first direction. The first side and the second side may be spaced apart from each other in a second direction that intersects the first direction. A first curved surface formed by the meeting of the bottom surface and the first side has a first radius of curvature, and a second curved surface formed by the meeting of the bottom surface and the second side has a second radius of curvature, wherein the second radius of curvature may be larger than the first radius of curvature.

[0012]

[0013] The pouch-type all-solid-state battery according to the embodiments of the present invention can prevent the electrode assembly from being damaged by the pouch outer material. Through this, the charge / discharge characteristics and lifespan characteristics of the pouch-type all-solid-state battery can be improved.

[0014] The all-solid-state battery pouch outer material according to embodiments of the present invention can prevent damage to the electrode assembly by minimizing interference with the electrode assembly. Specifically, it can prevent damage to the electrode assembly including first and second substrate tabs having different bending stiffnesses.

[0015]

[0016] FIG. 1 is a cross-sectional view of an all-solid-state battery according to one embodiment of the present invention.

[0017] FIG. 2 is a cross-sectional view of an all-solid-state battery according to one embodiment of the present invention.

[0018] FIG. 3a is a drawing showing a state in which an electrode assembly is accommodated in a pouch according to one embodiment of the present invention. FIG. 3b is a drawing showing a state in which an electrode assembly of a different form from FIG. 3a is accommodated in a pouch.

[0019] FIG. 4 is a schematic cross-section of a pouch-type all-solid-state battery according to one embodiment of the present invention.

[0020] FIG. 5 is a perspective view for explaining a pouch outer material according to one embodiment.

[0021] Figure 6a is a cross-sectional view along the line AA' of Figure 5.

[0022] FIG. 6b is a conceptual diagram illustrating the appearance of an electrode assembly accommodated in a pouch outer material according to one embodiment.

[0023] FIG. 6c is a conceptual diagram to explain the problem of a pouch-type all-solid-state battery that occurs when the first radius of curvature and the second radius of curvature are substantially the same.

[0024] FIG. 7 is a perspective view illustrating a pouch outer material according to another embodiment.

[0025] FIG. 8a is a cross-sectional view along the line BB' of FIG. 7. FIG. 8b is a cross-sectional view along the line C-C' of FIG. 7.

[0026] FIG. 8c is a conceptual diagram illustrating the difference in the radius of curvature between the first buffered surface, the second buffered surface, and the non-buffered surface.

[0027] FIG. 9 is a perspective view illustrating a pouch outer material according to another embodiment.

[0028] FIG. 10a is a cross-sectional view along the line DD' of FIG. 9. FIG. 10b is a cross-sectional view along the line E-E' of FIG. 9.

[0029] FIG. 11 is a perspective view illustrating a pouch outer material according to another embodiment.

[0030]

[0031] In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention are described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications can be made. The description of these embodiments is provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention.

[0032] In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention are described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications can be made. The description of these embodiments is provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention.

[0033] In this specification, when a component is described as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. Additionally, in the drawings, the thicknesses of the components are exaggerated for the effective description of the technical content. Throughout the specification, parts indicated by the same reference numeral represent the same components.

[0034] The embodiments described herein will be described with reference to cross-sectional and / or plan views, which are exemplary illustrations of the invention. In the drawings, the thicknesses of films and regions are exaggerated for effective description of the technical content. Accordingly, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions illustrated in the drawings are intended to illustrate specific forms of regions of the device and are not intended to limit the scope of the invention. Although terms such as first, second, third, etc., have been used to describe various components in the various embodiments of this specification, these components should not be limited by such terms. These terms are used merely to distinguish one component from another. The embodiments described and illustrated herein also include their complementary embodiments.

[0035] The terms used herein are for describing the embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used herein, 'comprises' and / or 'comprising' do not exclude the presence or addition of one or more other components to the mentioned components.

[0036] In this specification, each of the phrases such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof.

[0037]

[0038] FIG. 1 is a cross-sectional view of an all-solid-state battery (10) according to one embodiment of the present invention.

[0039] FIG. 1 is a cross-sectional view illustrating an all-solid-state battery according to embodiments of the present invention.

[0040] Referring to FIG. 1, the all-solid-state battery (10) may include a positive electrode layer (100), a negative electrode layer (200) facing the positive electrode layer (100), and a solid electrolyte layer (300) disposed between the positive electrode layer (100) and the negative electrode layer (200). However, not limited thereto, the all-solid-state battery (10) may further include an additional functional layer, such as an adhesion-enhancing layer, disposed between the positive electrode layer (100) and the solid electrolyte layer (300) or between the negative electrode layer (200) and the solid electrolyte layer (300).

[0041] The positive layer (100) may include a positive current collector (110) and a positive active material layer (120) disposed on the positive current collector (110). The positive active material layer (120) may include a positive active material, a solid electrolyte, a conductive material, and a binder.

[0042] The positive current collector (110) can provide a reference surface on which the positive active material layer (120) is placed. The positive current collector (110) may have a plate or foil form. For example, the positive current collector (110) may include indium (In), copper (Cu), magnesium (Mg), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof.

[0043] Unlike as illustrated in FIG. 1, in one embodiment of the present invention, the positive current collector (110) may be omitted. Although not illustrated, a carbon layer with a thickness of 0.1 μm to 4 μm may be further disposed between the positive current collector (110) and the positive active material layer (120) to increase the bonding strength between the positive current collector (110) and the positive active material layer (120).

[0044] The positive electrode active material may be a material capable of reversibly absorbing and desorbing lithium ions. For example, the positive electrode active material may include lithium transition metal oxides such as lithium cobalt oxide (LCO), lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt manganese oxide (NCM), lithium manganate, and lithium iron phosphate, nickel sulfide, copper sulfide, lithium sulfide, iron oxide, or vanadium oxide, but is not limited thereto. The positive electrode active material may be a single material or a mixture of two or more materials.

[0045] Lithium transition metal oxides are, for example, Li a A 1-b B b D2(0.90≤a≤1, 0≤b≤0.5), Li a E 1-b B 1 b O 2-c D c (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05), LiE 2-b B 1 b O 4-c D c (0≤b≤0.5, 0≤c≤0.05), Li a Ni 1-b-c Co b B 1 c D α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Ni 1-b-c Co b B 1 c O 2-α F 1 α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li aNi 1-b-c Mn b B 1 c D α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2), Li a Ni 1-b-c Mn b B 1 c O 2-α F 1 α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Ni b E c G d O2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1), Li a Ni b Co c Mn d GeO2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0.001≤e≤0.1), Li a NiG b O2(0.9≤a≤1, 0.001≤b≤0.1), Li a CoG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a MnG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a Mn2GbO4(0.90≤a≤1, 0.001≤b≤0.1), QO2, QS2, LiQS2, V2O5, LiV2O5, LiI 1 O2, LiNiVO4, Li 3-f J2(PO4)3(0≤f≤2), Li 3-f It may be a compound represented by either Fe2(PO4)3 (0≤f≤2) or LiFePO4. In such compounds, the uppercase "A" is Ni, Co, Mn, or a combination thereof, and the uppercase "B 1" is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements or combinations thereof, uppercase "D" is O, F, S, P, or a combination thereof, uppercase "E" is Co, Mn, or a combination thereof, and uppercase "F 1 " is F, S, P, or a combination thereof, uppercase "G" is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof, uppercase "Q" is Ti, Mo, Mn, or a combination thereof, and uppercase "I 1 " is Cr, V, Fe, Sc, Y, or a combination thereof, and uppercase "J" is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

[0046]

[0047] The positive electrode active material may include, for example, a lithium salt of a transition metal oxide having a layered rock salt type structure among the lithium transition metal oxides described above. The "layered rock salt type structure" is, for example, a cubic rock salt type structure. <111> It is a structure in which oxygen and metal atomic layers are alternately and regularly arranged in a specific direction, thereby forming a two-dimensional plane for each atomic layer. The "cubic rock salt type structure" represents a sodium chloride (NaCl) type structure, which is a type of crystal structure; specifically, it exhibits a structure in which face-centered cubic lattices (fcc) formed by cations and anions, respectively, are offset from each other by half the ridge of the unit lattice. Lithium transition metal oxides having such a layered rock salt type structure are, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mn zO2(NCM) (0 <x<1,0<y<1, 0<z<1, x+y+z=1) 등의 삼원계 리튬전이금속산화물일 수 있다. 양극 활물질이 층상암염형 구조를 갖는 삼원계 리튬전이금속산화물을 포함하는 경우, 전고체 전지(10)의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0048] The aforementioned compound contained in the positive electrode active material may be covered by a coating layer (not shown). The positive electrode active material may also be a mixture of the aforementioned compound and the compound to which the coating layer is added. Meanwhile, the coating layer added to the surface of the positive electrode active material may include, for example, oxides, hydroxides, oxyhydroxides, oxycarbonates, or hydroxycarbonates of the following coating elements. The compounds forming this coating layer may be amorphous or crystalline. The coating elements included in the coating layer may include Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof. The coating layer may include, for example, Li2O-ZrO2 (LZO). The method for forming the coating layer may be selected within a range that does not adversely affect the physical properties of the positive electrode active material. The method for forming the coating layer may include, for example, spray coating or immersion methods.

[0049] When the positive electrode active material is a ternary lithium transition metal oxide such as NCA or NCM and contains nickel (Ni), the capacity density of the all-solid-state battery (10) can be increased, and the metal leaching of the positive electrode active material in the charged state can be reduced. As a result, the cycle characteristics of the all-solid-state battery (10) in the charged state can be improved. Meanwhile, “cycle characteristics” is a characteristic that indicates the degree of deterioration of the all-solid-state battery (10) due to charging and discharging of the all-solid-state battery (10). An all-solid-state battery (10) with high cycle characteristics has a small degree of deterioration due to charging and discharging, while an all-solid-state battery (10) with low cycle characteristics may have a large degree of deterioration due to charging and discharging.

[0050] The shape of the positive electrode active material may include particle shapes such as spheres or ellipsoids. The particle size and content of the positive electrode active material are not particularly limited.

[0051] The solid electrolyte may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. Sulfide-based solid electrolytes include, for example, Li2S-P2S5, Li2S-P2S5-LiX (where X is a halogen element), Li2S-P2S5-Li2O, Li2S-P2S5-Li2O-LiI, Li2S-SiS2, Li2S-SiS2-LiI, Li2S-SiS2-LiBr, Li2S-SiS2-LiCl, Li2S-SiS2-B2S3-LiI, Li2S-SiS2-P2S5-LiI, Li2S-B2S3, and Li2S-P2S5-Z m S n (m, n are positive numbers, uppercase “Z” is one of Ge, Zn, or Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q (p, q are positive numbers, uppercase “M” is one of P, Si, Ge, B, Al, Ga, In), Li 7-x PS 6-x Cl x(0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I x It may include at least one selected from (0≤x≤2).

[0052] Sulfide-based solid electrolytes are, for example, Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I x It may be an argyrodite-type compound comprising one or more selected from (0≤x≤2). In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound comprising one or more selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I. The density of the argyrodite-type solid electrolyte may be 1.5 g / cc to 2.0 g / cc. By having a density of 1.5 g / cc or higher for the argyrodite-type solid electrolyte, the internal resistance of the all-solid-state battery is reduced, and defects such as penetration and short circuit of the solid electrolyte film due to lithium dendrite formation can be prevented. The elastic modulus of the solid electrolyte may be, for example, 15 GPa to 35 GPa.

[0053] Alternatively, sulfide-based solid electrolytes are Li 7-a-c M a PS 6-c X cIt may be an argyrodite-type compound containing (0≤a≤2, (0≤c≤2)). Here, X may be F, Br, Cl, or a combination thereof. M may be candium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), mercury (Hg), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi), or a combination thereof.

[0054] The solid electrolyte included in the positive electrode active material layer (120) may have a smaller average particle size (D50) compared to the solid electrolyte included in the solid electrolyte layer (300). For example, the average particle size (D50) of the solid electrolyte included in the positive electrode active material layer (120) may be 90% or less, 80% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, or 20% or less of the average particle size (D50) of the solid electrolyte included in the solid electrolyte layer (300). Meanwhile, the average particle size (D50) may be a median diameter measured using a laser particle size distribution meter.

[0055] The positive active material layer (120) may include a conductive material. The conductive material may have conductivity without causing chemical changes in the all-solid-state battery (10), thereby increasing the conductivity of the positive active material and the solid electrolyte. The conductive material may include a carbon-based material. The conductive material may include, for example, one or more selected from graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes.

[0056] The positive active material layer (120) may further include a binder. The binder may include a material for bonding the positive active material, solid electrolyte, and conductive material included in the positive active material layer (120), and for improving the bonding strength with the positive current collector (110). For example, the binder may include polyvinylidene fluoride, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, or polymethyl methacrylate.

[0057] When the total of the positive active material, solid electrolyte, conductive material, and binder is 100 parts by weight, the positive active material layer (120) may include 85 to 92 parts by weight of the positive active material. The positive active material layer (120) may include 0.5 to 1.5 parts by weight of the binder.

[0058] In the positive electrode active material layer (120), the conductive material may have 1 to 50 parts by weight per 100 parts by weight of solid electrolyte. If the conductive material is less than 1 part by weight per 100 parts by weight of solid electrolyte, the electrical conductivity of the positive electrode active material layer (120) may be reduced. If the conductive material is more than 50 parts by weight per 100 parts by weight of solid electrolyte, the ratio of the conductive material is excessively high, so a coating layer covering the surface of the solid electrolyte may not be properly formed.

[0059] According to the embodiments, the positive active material layer (120) may further include at least one additive selected from the group consisting of a filler, a coating agent, a dispersant, and an ion-conducting aid, in addition to the positive active material, solid electrolyte, conductive material, and binder described above.

[0060] The solid electrolyte layer (300) is disposed between the positive electrode layer (100) and the negative electrode layer (200) and may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. The solid electrolyte included in the solid electrolyte layer (300) may be the same as or different from any one of the materials that may be included in the solid electrolyte included in the aforementioned positive electrode active material layer (120).

[0061] The solid electrolyte layer (300) may further include a binder. The binder in the solid electrolyte layer (300) is not limited to, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc. The binder of the solid electrolyte layer (300) may be the same as or different from the binder included in the positive active material layer (120) or the binder included in the coating layer (220).

[0062] The negative electrode layer (200) may include a negative electrode current collector (210) and a coating layer (220) on the negative electrode current collector (210). The negative electrode current collector (210) may provide a reference surface on which the coating layer (220) is placed. The negative electrode current collector (210) may include, for example, a material that does not react with lithium, that is, does not form any alloys or compounds with lithium. For example, the negative electrode current collector (210) may include at least one metal selected from the group consisting of copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni). The thickness of the negative electrode current collector (210) may be 1 μm to 20 μm, more specifically 5 μm to 15 μm, and more specifically 7 μm to 10 μm.

[0063] The negative current collector (210) may be composed of one of the metals described above, or may include an alloy of two or more metals or a coating material. The negative current collector (210) may, for example, have a plate-like or foil-like shape. Meanwhile, in one embodiment, the negative current collector (210) may be omitted.

[0064] The coating layer (220) can allow lithium metal to grow between the all-solid-state battery (10) and the negative current collector (210) during charging. The coating layer (220) can serve as a protective layer for the lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites.

[0065] The coating layer (220) may include metal and carbon. For example, the coating layer (220) may include at least one metal selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). The coating layer (220) may include at least one carbon selected from the group consisting of carbon black, acetylene black, furnace black, ketjen black, and graphene. In one embodiment, the coating layer (220) may include a mixture of carbon black and silver (Ag).

[0066] The coating layer (220) may further include other additives in addition to metal and carbon. The coating layer (220) may further include at least one additive selected from the group consisting of, for example, binders, fillers, coating agents, dispersants, and ion-conducting aids.

[0067] The coating layer (220) may have a smaller thickness compared to the positive active material layer (120). The thickness of the coating layer (220) may be, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or 5% or less of the thickness of the positive active material layer (120). The thickness of the coating layer (220) may be, for example, 1 µm to 20 µm, 2 µm to 10 µm, or 3 µm to 7 µm. If the thickness of the coating layer (220) is excessively thin, lithium dendrites formed between the coating layer (220) and the negative current collector (210) may cause the coating layer (220) to collapse, thereby degrading the cycle characteristics of the all-solid-state battery (10). If the thickness of the coating layer (220) increases excessively, the energy density of the all-solid-state battery (10) decreases and the internal resistance of the all-solid-state battery (10) due to the coating layer (220) increases, which may degrade the cycle characteristics of the all-solid-state battery (10).

[0068] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the coating layer (220) and the solid electrolyte layer (300).

[0069] In one embodiment, the solid electrolyte layer (300) may include an anode solid electrolyte layer (310) and a cathode solid electrolyte layer (320). The anode solid electrolyte layer (310) may be adjacent to the anode layer (100), and the cathode solid electrolyte layer (320) may be adjacent to the cathode layer (200). Each of the anode solid electrolyte layer (310) and the cathode solid electrolyte layer (320) may include the solid electrolyte described above.

[0070] FIG. 2 is a cross-sectional view illustrating an all-solid-state battery according to another embodiment. The description of features common to the all-solid-state battery described above with reference to FIG. 1 is omitted, and the differences are described in detail.

[0071] Referring to Fig. 2, the all-solid-state battery may be a bicell type all-solid-state battery (BCL).

[0072] A solid-state battery (BCL) may include a positive electrode layer (100); a first solid electrolyte layer (3001) on one side of the positive electrode layer (100); a first negative electrode layer (2001) on the first solid electrolyte layer (3001); a second solid electrolyte layer (3002) on the other side of the positive electrode layer (100); and a second negative electrode layer (2002) on the second solid electrolyte layer (3002).

[0073] In one embodiment, the positive layer (100) may include a positive current collector (110); a first positive active material layer (1201) on one side of the positive current collector (110); and a second positive active material layer (1202) on the other side of the positive current collector (110). Each of the first and second positive active material layers (1201, 1202) is the same as described above for the positive active material layer (120) with reference to FIG. 1.

[0074] In one embodiment, the first cathode layer (2001) may include a first cathode current collector (2101); and a first coating layer (2201) on the first cathode current collector (2101). The first coating layer (2201) may be in contact with the first solid electrolyte layer (3001).

[0075] In one embodiment, the second cathode layer (2002) may include a second cathode current collector (2102); and a second coating layer (2202) on the second cathode current collector (2102). The second coating layer (2202) may be in contact with the second solid electrolyte layer (3002).

[0076] Each of the first and second cathode layers (2001, 2002) is the same as described above for the cathode layer (200) with reference to FIG. 1.

[0077] In one embodiment, the anode layer (100) may include an anode tab. A plurality of anode tabs included in the electrode assembly described below may be electrically connected to form an anode substrate tab.

[0078] In one embodiment, each of the first and second cathode layers (2001, 2002) may include a cathode tab. A plurality of cathode tabs included in the electrode assembly described below may be electrically connected to form a cathode substrate tab.

[0079] In one embodiment, the first solid electrolyte layer (3001) may include a first anode solid electrolyte layer (3101) and a first cathode solid electrolyte layer (3201). The first cathode solid electrolyte layer (3201) may be in contact with the first coating layer (2201).

[0080] In one embodiment, the second solid electrolyte layer (3002) may include a second anode solid electrolyte layer (3102) and a second cathode solid electrolyte layer (3202). The second cathode solid electrolyte layer (3202) may be in contact with the second coating layer (2202).

[0081] Each of the first and second solid electrolyte layers (3001, 3002) is the same as described above for the solid electrolyte layer (300) with reference to FIG. 1.

[0082]

[0083] FIG. 3a is a diagram showing a state in which an electrode assembly is accommodated in a pouch according to one embodiment. FIG. 3b is a diagram showing a state in which an electrode assembly of a different form from FIG. 3a is accommodated in a pouch. FIG. 4 is a diagram schematically illustrating a cross-section of a pouch-type all-solid-state battery according to one embodiment of the present invention.

[0084] Referring to FIGS. 3a and 4, the all-solid-state battery (PCL) may include a pouch casing (PCH) and an electrode assembly (ESA) in which at least one unit cell is stacked. The electrode assembly (ESA) may be received in a receiving portion (REP) of the pouch casing (PCH).

[0085] In one embodiment, the pouch outer material (PCH) may be configured such that a first outer material (POH1) and a second outer material (POH2) face each other to package an electrode assembly (ESA). For example, the pouch outer material (PCH) may be formed by arranging a first outer material (POH1) capable of accommodating at least a portion of the electrode assembly (ESA) and a second outer material (POH2) capable of accommodating the remaining portion of the electrode assembly (ESA) to face each other. The first outer material (POH1) may surround a portion of the electrode assembly (ESA) to form a first outer material region of the pouch-type all-solid-state battery, and the second outer material (POH2) may surround the remaining portion of the electrode assembly (ESA) to form a second outer material region of the pouch-type all-solid-state battery. For example, the first outer material (POH1) may surround the upper portion of the electrode assembly (ESA) to form a first outer material region of the pouch-type all-solid-state battery. The second outer layer (POH2) can surround the lower part of the electrode assembly (ESA) and form the second outer layer region of the pouch-type all-solid-state battery.

[0086] As another example, although not illustrated, the pouch outer material (PCH) may be formed by arranging a first outer material (POH1) capable of accommodating the entire electrode assembly (ESA) and a second outer material (POH2) capable of serving as a cover for the second outer material to face each other. That is, the first outer material (POH1) can form the first outer material region of the pouch-type all-solid-state battery by wrapping the remaining surfaces of the electrode assembly, excluding the upper or lower surface.

[0087] The first outer edge (EDG1) of the first outer material (POH1) and the second outer edge (EDG2) of the second outer material (POH2) are subsequently sealed, thereby allowing the electrode assembly to be sealed.

[0088] In this specification, the term "unit cell" may refer to a basic unit comprising components that constitute a cell. For example, a unit cell may include a first electrode, a second electrode having opposite polarity to the first electrode, and a solid electrolyte layer between the first and second electrodes. The first electrode may include a first electrode current collector (PLT1) and a first electrode coating layer and / or a first electrode active material layer formed on the first electrode current collector (PLT1), and the second electrode may include a second electrode current collector (PLT2) and a second electrode coating layer and / or a second electrode active material layer formed on the second electrode current collector (PLT2).

[0089] In one embodiment, the unit cell may include a positive electrode layer (100), a negative electrode layer (200), and a solid electrolyte layer (300) between the positive electrode layer (100) and the negative electrode layer (200). Here, the positive electrode layer (100), the negative electrode layer (200), and the solid electrolyte layer (300) may be identical to the configuration of the all-solid-state battery (10) described in FIG. 1. Also, in one embodiment, the first electrode current collector (PLT1) may be a positive electrode current collector (110) and the second electrode current collector (PLT2) may be a negative electrode current collector (200), or they may be opposite to each other.

[0090] In one embodiment, the unit cell may include an anode layer (100); a first solid electrolyte layer (3001) on one side of the anode layer (100); a first cathode layer (2001) on the first solid electrolyte layer (3001); a second solid electrolyte layer (3002) on the other side of the anode layer (100); and a second cathode layer (2002) on the second solid electrolyte layer (3002). Here, the anode layer (100), the first cathode layer (2001), the second cathode layer (2002), the first solid electrolyte layer (3001), and the second solid electrolyte layer (3002) may be identical to the configuration of the all-solid-state battery (BCL) described in FIG. 2. In addition, in one embodiment, the first electrode current collector (PLT1) may be an anode current collector (110) and the second electrode current collector (PLT2) may be a cathode current collector (200), or they may be opposite to each other.

[0091] The electrode assembly (ESA) may include a unit cell and a substrate tab (TB) electrically connected to the unit cell. In one embodiment, the substrate tab (TB) may be electrically connected to an electrode current collector and may protrude from the electrode current collector. For example, a first substrate tab (TB1) may be electrically connected to a first electrode current collector (PLT1), and a second substrate tab (TB2) may be electrically connected to a second electrode current collector (PLT2).

[0092] In one embodiment, the first substrate tab (TB1) may include a plurality of positive tabs or a plurality of negative tabs as described above with reference to FIG. 2. For example, the first substrate tab (TB1) may include a plurality of positive tabs.

[0093] In one embodiment, a plurality of positive tabs can be electrically connected to each other by welding.

[0094] In one embodiment, the second substrate tab (TB2) may include electrode tabs having a polarity different from that of the first substrate tab (TB1). As an example, it may include a plurality of negative tabs as described above with reference to FIG. 2.

[0095] In one embodiment, a plurality of cathode tabs can be electrically connected to each other by welding.

[0096] A pouch-type all-solid-state battery (PCL) may include a lead tab (LTB) connected to a substrate tab (TB). The lead tab (LTB) may be electrically connected to the substrate tab (TB) and protrude outside the pouch outer casing (PCH). In other words, the lead tab (LTB) may be configured so that the electrode assembly (ESA) is electrically connected to the outside of the pouch outer casing (PCH). The method of electrical connection is not particularly limited, and methods such as welding, soldering, or brazing may be used.

[0097] The electrode assembly (ESA) may further include at least one elastic pad (ELM). The elastic pad (ELM) may be disposed between unit cells. Additionally, the elastic pad (ELM) may be disposed on the top surface and the bottom surface, respectively, of the electrode assembly (ESA).

[0098] The elastic pad (ELM) can facilitate good contact between solid components to ensure uniform pressure distribution within the electrode assembly (ESA), and also serve to relieve stress transmitted to the solid electrolyte. Additionally, the elastic pad (ELM) can prevent cracks from forming in the solid electrolyte caused by stress accumulation due to changes in the thickness of the unit cell during charging and discharging.

[0099] The material of the elastic pad (ELM) is not particularly limited as long as it is a material capable of shrinking and expanding in response to changes in the thickness of the unit cell. In one embodiment, the elastic pad (ELM) may include an acrylic resin, a urethane resin, a silicone resin, or a combination thereof.

[0100] In one embodiment, the elastic pad (ELM) may have a single layer or a multilayer structure.

[0101] Referring again to FIG. 3a, in one embodiment, the first substrate tab (TB1) and the second substrate tab (TB2) may be formed in different directions. For example, the first substrate tab (TB1) and the second substrate tab (TB2) may be formed in opposite directions and aligned along the second direction (D2).

[0102] Referring to FIG. 3b, in one embodiment, the first substrate tab (TB1) and the second substrate tab (TB2) may be formed in the same direction. For example, the first substrate tab (TB1) and the second substrate tab (TB2) may be formed in the same direction and may be spaced apart from each other in a first direction (D1).

[0103]

[0104] FIG. 5 is a perspective view illustrating a pouch outer material according to one embodiment. FIG. 6a is a cross-sectional view along the line AA' of FIG. 5. Referring to FIG. 3a and FIG. 5, the pouch outer material (PCH) includes a recessed receiving portion (REP), and an electrode assembly (ESA) can be received in the receiving portion (REP).

[0105] In one embodiment, the electrode assembly (ESA) may include the first substrate tab (TB1) and the second substrate tab (TB2) described above with reference to FIG. 3a and FIG. 4.

[0106] In one embodiment, the first substrate tab (TB1) may be either an anode substrate tab or a cathode substrate tab, and the second substrate tab (TB2) may be the other one among the anode substrate tab and the cathode substrate tab. The anode substrate tab may include a plurality of anode tabs (PTB). The cathode substrate tab may include a plurality of cathode tabs (NTB). As an example, referring to FIG. 6b described below, the first substrate tab (TB1) may include a plurality of anode tabs (PTB), and the second substrate tab (TB2) may include a plurality of cathode tabs (NTB).

[0107] Referring again to FIGS. 3a, 3b, and FIG. 5, in one embodiment, the pouch outer material (PCH) may include a receiving portion (REP). An electrode assembly (ESA) may be received in the receiving portion (REP) of the pouch outer material (PCH). The receiving portion of the pouch outer material (PCH) may include a bottom surface (BOS) on which the electrode assembly (ESA) is seated, and a side wall (SIW) surrounding the bottom surface (BOS). The side wall (SIW) may include a first side (SID1), a second side (SID2), a third side, and a fourth side. The bottom surface (BOS) and the first side (SID1), the second side (SID2), the third side, and the fourth side may be inner surfaces of the pouch outer material (PCH).

[0108] In one embodiment, the first side (SID1) and the second side (SID2) may each extend in a first direction (D1). The first side (SID1) and the second side (SID2) may be spaced apart from each other in a second direction (D2).

[0109] In one embodiment, the third side and the fourth side may each extend in a second direction (D2). The third side and the fourth side may be spaced apart from each other in a first direction (D1).

[0110] In one embodiment, the length of the first side (SID1) in the first direction (D1) may be smaller than the length of each of the third and fourth sides in the second direction (D2).

[0111] In one embodiment, the length of the second side (SID2) in the first direction (D1) may be smaller than the length of each of the third and fourth sides in the second direction (D2).

[0112] FIG. 6b is a conceptual diagram illustrating the appearance of an electrode assembly accommodated in a pouch outer material according to one embodiment.

[0113] Referring to FIG. 6b, in one embodiment, the second substrate tab (TB2) may have greater bending stiffness than the first substrate tab (TB1). As a result, the second substrate tab (TB2) may be bent incompletely compared to the first substrate tab (TB1). That is, unlike the positive tabs (PTB) constituting the first substrate tab (TB1), the negative tabs (NTB) constituting the second substrate tab (TB2) may not be completely folded and may have a gentle slope.

[0114] For example, the number of negative tabs (NTB) included in the second substrate tab (TB2) may be greater than the number of positive tabs (PTB) included in the first substrate tab (TB1). As a result, the second substrate tab (TB2) may have greater bending stiffness than the first substrate tab (TB1). For example, the electrode assembly (ESA) includes a bicell-type all-solid-state battery (BCL) as described above with reference to FIG. 2, so that the number of negative tabs (NTB) included in the second substrate tab (TB2) is greater than the number of positive tabs (PTB) included in the first substrate tab (TB1), and consequently, the bending stiffness of the second substrate tab (TB2) may be greater than the bending stiffness of the first substrate tab (TB1).

[0115] For example, the bending stiffness of each of the cathode tabs (NTB) included in the second substrate tab (TB2) may be greater than the bending stiffness of each of the anode tabs (PTB) included in the first substrate tab (TB1). For example, the cathode tab (NTB) may be made of stainless steel (SUS) material, and the anode tab (PTB) may be made of aluminum or an aluminum alloy material, so that the bending stiffness of the cathode tab (NTB) may be greater than the bending stiffness of the anode tab (PTB). Consequently, the bending stiffness of the second substrate tab (TB2) may be greater than the bending stiffness of the first substrate tab (TB1).

[0116] As described in the above embodiments, if the second substrate tab (TB2) has greater bending rigidity than the first substrate tab (TB1), it may be necessary to secure a larger space within the receiving portion (REP) of the pouch outer material (PCH). In particular, during the vacuum sealing process of the pouch outer material, the pouch outer material (PCH) may be adsorbed to the electrode assembly (ESA), and at this time, it is necessary to prevent excessive force from being applied to the electrode assembly (ESA), including the second substrate tab (TB2).

[0117] Again, referring to FIGS. 5 and 6a, the receiving portion of the pouch outer material (PCH) may include a first curved portion (CSP1) formed by the meeting of a bottom surface (BOS) and a first side surface (SID1), and may include a second curved portion (CSP2) formed by the meeting of a bottom surface (BOS) and a second side surface.

[0118] In one embodiment, the first curved surface (CSP1) may have a first radius of curvature (R1), and the second curved surface (CSP2) may have a second radius of curvature (R2).

[0119] In one embodiment, the second radius of curvature (R2) may be larger than the first radius of curvature (R1).

[0120] Referring to FIG. 3b and FIG. 5, in one embodiment, the first substrate tab (TB1) and the second substrate tab (TB2) of the electrode assembly (ESA) housed in the pouch outer material (PCH) may be formed in the same direction. The first substrate tab (TB1) and the second substrate tab (TB2) may protrude in the second direction (D2) and may be spaced apart from each other along the first direction (D1). For example, the first substrate tab (TB1) and the second substrate tab (TB2) of the electrode assembly (ESA) may be adjacent to the second side (SID2) of the pouch outer material (PCH).

[0121] By making the radius of curvature (R2) of the second curved portion (CSP2) adjacent to the first substrate tab (TB1) and the second substrate tab (TB2) larger than the radius of curvature (R1) of the first curved portion (CSP1) not adjacent to the first and second substrate tabs (TB1, TB2), it is possible to prevent the pouch outer material (PCH) from applying excessive impact to the first substrate tab (TB1), the second substrate tab (TB2), and the solid electrolyte layer inside the electrode assembly during the vacuum sealing process of the pouch outer material.

[0122]

[0123] Referring again to FIG. 3a and FIG. 5, in another embodiment, the first substrate tab (TB1) and the second substrate tab (TB2) of the electrode assembly (ESA) housed in the pouch outer material (PCH) may be formed in different directions. The first substrate tab (TB1) and the second substrate tab (TB2) of the electrode assembly (ESA) may be aligned with each other along a second direction (D2). For example, the first side (SID1) of the pouch outer material (PCH) may be adjacent to the first substrate tab (TB1) of the electrode assembly (ESA), and the second side (SID2) may be adjacent to the second substrate tab (TB2) of the electrode assembly (ESA).

[0124] By making the radius of curvature (R2) of the second curved portion (CSP2) adjacent to the second substrate tab (TB2), which has relatively high bending stiffness, larger than the radius of curvature (R1) of the first curved portion (CSP1) adjacent to the first substrate tab (TB1), which has relatively low bending stiffness, it is possible to prevent the pouch outer material (PCH) from applying excessive impact to the second substrate tab (TB2) and the solid electrolyte layer inside the electrode assembly during the vacuum sealing process of the pouch outer material. For example, the first radius of curvature (R1) may be 0.1 mm to 0.6 mm. The second radius of curvature (R2) may be 0.2 mm to 1.2 mm.

[0125] Each of the unit cells constituting the electrode assembly (ESA) may include a solid electrolyte layer containing a sulfide-based solid electrolyte. There is a risk that cracks may occur in the sulfide-based solid electrolyte due to interference from the pouch outer material (PCH) during the vacuum sealing process of the pouch outer material (PCH). By making the second radius of curvature (R2) of the pouch outer material (PCH) according to the above embodiment larger than the first radius of curvature (R1), internal damage to the electrode assembly caused by the pouch outer material (PCH) can be prevented, and in particular, cracks in the solid electrolyte layer within the electrode assembly can be prevented.

[0126] FIG. 6c is a conceptual diagram for explaining the problem of a pouch-type all-solid-state battery that occurs when the first radius of curvature (R1) and the second radius of curvature (R2) are substantially the same.

[0127] Referring to FIG. 6c, as described above with reference to FIG. 6b, the second substrate tab (TB2) may have greater bending rigidity than the first substrate tab (TB1). As a result, the second substrate tab (TB2) may be bent incompletely compared to the first substrate tab (TB1). If the second radius of curvature (R2) is made smaller to match the first radius of curvature (R1), the pouch outer material (PCH) may be excessively adhered to the second substrate tab (TB2) and the electrode assembly (ESA) containing it during vacuum sealing, thereby damaging the electrode assembly.

[0128] Conversely, if the first radius of curvature (R1) is increased to match the second radius of curvature (R2), the first side (SID1) space adjacent to the first substrate tab (TB1) remains excessively large, which may cause wrinkles to form on the pouch outer material (PCH) after vacuum sealing. This may cause unnecessary contact between the pouch outer material (PCH) and the electrode assembly (ESA), and consequently, damage to the electrode assembly (ESA).

[0129] In one embodiment, the first radius of curvature (R1) may be 0.1 mm to 0.6 mm.

[0130] In one embodiment, the second radius of curvature (R2) may be 0.2 mm to 1.2 mm.

[0131] On the other hand, as described above with reference to FIGS. 5a and 5b, a pouch-type all-solid-state battery according to embodiments of the present invention can prevent damage to the electrode assembly by making the second radius of curvature (R2) of the receiving portion of the pouch outer material (PCH) larger than the first radius of curvature (R1).

[0132]

[0133] FIG. 7 is a perspective view illustrating a pouch outer material according to another embodiment. FIG. 8a is a cross-sectional view along the line BB' of FIG. 7. FIG. 8b is a cross-sectional view along the line C-C' of FIG. 7. Descriptions of parts common to those described with reference to FIG. 5 and FIG. 6a are omitted, and descriptions will focus on the differences.

[0134] Referring to FIG. 7, the receiving portion of the pouch outer material (PCH) may include a bottom surface (BOS) on which an electrode assembly is seated, and a side wall (SIW) surrounding the bottom surface (BOS). The side wall (SIW) may include a first side (SID1), a second side (SID2), a third side, and a fourth side.

[0135] A bottom surface (BOS) and a first side (SID1) may meet to form a first curved surface (CSP1), and a bottom surface (BOS) and a second side (SID2) may meet to form a second curved surface (CSP2).

[0136] Each of the first side (SID1) and the second side (SID2) may include a buffer region (BRG) adjacent to the first and second recording tabs (TB1). Each of the first side (SID1) and the second side (SID2) may further include a non-buffer region (NRG) which is a region other than the buffer region (BRG). For example, the first side (SID1) may include a first buffer region (BRG1) and may further include a first non-buffer region (NRG1). The second side (SID2) may include a second buffer region (BRG2) and may further include a second non-buffer region (NRG2).

[0137] Referring to FIGS. 7 and FIGS. 8a, the first buffer region (BRG1) may meet the bottom surface (BOS) to form the first buffer curved surface (BSP1). The second buffer region (BRG2) may meet the bottom surface (BOS) to form the second buffer curved surface (BSP2).

[0138] Referring to FIGS. 7 and FIGS. 8b, the first non-buffered region (NRG1) may meet the bottom surface (BOS) to form the first non-buffered curved surface (NSP1). The second non-buffered region (NRG2) may meet the bottom surface (BOS) to form the second non-buffered curved surface (NSP2).

[0139] The first buffered surface portion (BSP1) and the first non-buffered surface portion (NSP1) can constitute the first surface portion (CSP1) described above.

[0140] The second buffered surface portion (BSP2) and the second non-buffered surface portion (NSP2) can constitute the second surface portion (CSP2) described above.

[0141] In one embodiment, the first cushioning surface (BSP1) may have a first cushioning radius of curvature (BR1), and the second cushioning surface (BSP2) may have a second cushioning radius of curvature (BR2). Each of the first and second non-cushioning surfaces (NSP1, NSP2) may have a non-cushioning radius of curvature (NR).

[0142] FIG. 8c is a conceptual diagram illustrating the difference in the radius of curvature between the first buffered surface, the second buffered surface, and the non-buffered surface.

[0143] Referring to FIG. 7 and FIG. 8c, in one embodiment, the second buffer radius of curvature (BR2) may be larger than the first buffer radius of curvature (BR1). The first buffer radius of curvature (BR1) may be larger than the non-buffer radius of curvature (NR).

[0144] Referring again to FIG. 3a and FIG. 7, in one embodiment, the first substrate tab (TB1) of the electrode assembly (ESA) may be adjacent to the first buffer region (BRG1). The second substrate tab (TB2) of the electrode assembly (ESA) may be adjacent to the second buffer region (BRG2).

[0145] By making the second buffer radius of curvature (BR2) larger than the first buffer radius of curvature (BR1), it is possible to prevent the pouch outer material (PCH) from applying excessive impact to the second substrate tab (TB2), which has relatively high bending rigidity, during the vacuum sealing process of the pouch outer material. Through this, damage to the solid electrolyte layer inside the electrode assembly can be prevented. For example, the first buffer radius of curvature (BR1) may be 0.1 mm to 0.6 mm. The second buffer radius of curvature (BR2) may be 0.2 mm to 1.2 mm.

[0146] In addition, by making the radius of curvature (NR) of the non-buffering curved portion (NSP) not adjacent to the first and second substrate tabs (TB1, TB2) smaller than the first buffering radius of curvature (BR1), the occurrence of wrinkles due to empty space can be prevented. For example, the non-buffering radius of curvature (NR) may be 0.01 mm to 0.55 mm.

[0147]

[0148] FIG. 9 is a perspective view illustrating a pouch outer material according to another embodiment. FIG. 10a is a cross-sectional view along the line DD' of FIG. 9. FIG. 10b is a cross-sectional view along the line E-E' of FIG. 9. Descriptions of parts common to those described with reference to FIG. 5 to FIG. 8c will be omitted, and descriptions will focus on the differences.

[0149] Referring to FIG. 9, the receiving portion of the pouch outer material (PCH) may include a bottom surface (BOS) on which an electrode assembly is seated, and a side wall (SIW) surrounding the bottom surface (BOS). The side wall (SIW) may include a first side (SID1), a second side (SID2), a third side, and a fourth side.

[0150] The first side (SID1) may include a non-buffered area (NRG). The second side (SID2) may include a buffered area (BRG) adjacent to the first and second record tabs (TB1). For example, the first side (SID1) may include a non-buffered area (NRG). The second side (SID2) may include a first buffered area (BRG1) and a second buffered area (BRG2).

[0151] Referring to FIGS. 9 and FIGS. 10a, the first buffer region (BRG1) may meet the bottom surface (BOS) to form the first buffered curved surface (BSP1). The non-buffer region (NRG) may meet the bottom surface (BOS) to form the non-buffered curved surface (NSP).

[0152] Referring to FIGS. 9 and FIGS. 10b, the second buffer region (BRG2) can meet the bottom surface (BOS) to form the second buffer curved surface (BSP2).

[0153] The non-buffering surface portion (NSP) can constitute the first surface portion (CSP1) described above.

[0154] The first buffered surface portion (BSP1) and the second buffered surface portion (BSP2) can constitute the second surface portion (CSP2) described above.

[0155] In one embodiment, the first cushioning surface (BSP1) may have a first cushioning radius of curvature (BR1), and the second cushioning surface (BSP2) may have a second cushioning radius of curvature (BR2). The non-cushioning surface (NSP) may have a non-cushioning radius of curvature (NR).

[0156] In one embodiment, the second buffer radius of curvature (BR2) may be larger than the first buffer radius of curvature (BR1). The first buffer radius of curvature (BR1) may be larger than the non-buffer radius of curvature (NR).

[0157] For example, the first cushioning radius of curvature (BR1) may be 0.1 mm to 0.6 mm. The second cushioning radius of curvature (BR2) may be 0.2 mm to 1.2 mm. The non-cushioning radius of curvature (NR) may be 0.01 mm to 0.55 mm.

[0158] By making the second buffer radius of curvature (BR2) larger than the first buffer radius of curvature (BR1), it is possible to prevent the pouch outer material (PCH) from applying excessive impact to the second substrate tab (TB2), which has relatively high bending rigidity, during the vacuum sealing process of the pouch outer material. Through this, damage to the solid electrolyte layer inside the electrode assembly can be prevented. In addition, by making the radius of curvature (NR) of the non-buffered curved portion (NSP) not adjacent to the first and second substrate tabs (TB1, TB2) smaller than the first buffer radius of curvature (BR1), the occurrence of wrinkles due to empty space can be prevented.

[0159]

[0160] FIG. 11 is a perspective view for explaining a pouch outer material according to another embodiment. The description of parts common to those described with reference to FIG. 9 to FIG. 10b will be omitted, and the description will focus on the differences.

[0161] The second side (SID2) may include a first buffer region (BRG1) adjacent to the first substrate tab (TB1) and a second buffer region (BRG2) adjacent to the second substrate tab (TB2). The second side (SID2) may further include a second non-buffered region (NRG2) which is a region other than the first and second buffer regions (BRG1, BRG2). For example, the first side (SID1) may include a non-buffered region (NRG).

[0162] The first buffer region (BRG1), the second buffer region (BRG2), and the second non-buffer region (NRG2) can constitute the second curved surface (NSP2) described above.

[0163] In one embodiment, the second cushioning radius of curvature (BR2) may be larger than the first cushioning radius of curvature (BR1). The first cushioning radius of curvature (BR1) may be larger than the non-cushioning radius of curvature (NR). For example, the first cushioning radius of curvature (BR1) may be 0.1 mm to 0.6 mm. The second cushioning radius of curvature (BR2) may be 0.2 mm to 1.2 mm. The non-cushioning radius of curvature (NR) may be 0.01 mm to 0.55 mm.

[0164] By making the second buffer radius of curvature (BR2) larger than the first buffer radius of curvature (BR1), it is possible to prevent the pouch outer material (PCH) from applying excessive impact to the second substrate tab (TB2), which has relatively high bending rigidity, during the vacuum sealing process of the pouch outer material. Through this, damage to the solid electrolyte layer inside the electrode assembly can be prevented. In addition, by making the radius of curvature (NR) of the non-buffered curved portion (NSP) not adjacent to the first and second substrate tabs (TB1, TB2) smaller than the first buffer radius of curvature (BR1), the occurrence of wrinkles due to empty space can be prevented.

[0165]

[0166] Hereinafter, a method for manufacturing a pouch-type all-solid-state battery according to one embodiment is described.

[0167] A method for manufacturing a pouch-type all-solid-state battery according to one embodiment may include: accommodating an electrode assembly (ESA) in a pouch outer material (PCH); and sealing the outer edge of the pouch outer material.

[0168] Referring to FIG. 3 and FIG. 5b, in one embodiment, an electrode assembly (ESA) can be accommodated in a receiving portion (REP) of a pouch outer material (PCH). Specifically, the electrode assembly (ESA) can be positioned within the pouch outer material (PCH) such that a first substrate tab (TB1) of the electrode assembly (ESA) is adjacent to a first side (SID1) of the pouch outer material (PCH), and a second substrate tab (TB2) of the electrode assembly (ESA) is adjacent to a second side (SID2) of the pouch outer material (PCH).

[0169] In one embodiment, as described above with reference to FIGS. 6a and 6b, a first curved surface (CSP1) formed by the meeting of the bottom surface (BOH) of the receiving portion (REP) and the first side surface (SID1) may have a first radius of curvature (R1), and a second curved surface (CSP2) formed by the meeting of the bottom surface (BOH) of the receiving portion (REP) and the second side surface (SID2) may have a second radius of curvature (R2). The second radius of curvature (R2) may be larger than the first radius of curvature (R1).

[0170] In an embodiment of the present invention, the receiving portion (REP) may be in a rectangular shape or a rectangular shape with four rounded corners, but is not necessarily limited thereto. The shape of the receiving portion (REP) may be changed to correspond to the shape of the electrode assembly (ESA).

[0171] In one embodiment, a method for manufacturing a pouch-type all-solid-state battery may include sealing the outer edge of a pouch outer material (PCH). In one embodiment, the sealing may be performed by a heat fusion method.

[0172] In one embodiment, the sealing may be performed while applying pressure to the receiving portion (REP) in which the electrode assembly is received. As a result, the electrode assembly (ESA) may be compressed.

[0173] In one embodiment, the receiving portion (REP) may be pressurized by a sealing pressure (SP). The sealing pressure (SP) may be 0.5 MPa to 3 MPa, and specifically 0.5 MPa to 1 MPa.

[0174] In one embodiment, the sealing may be performed in a vacuum. As described above, by having a second radius of curvature (R2) greater than the first radius of curvature (R1), damage to the second substrate tab (TB2) with high bending stiffness and the electrode assembly (ESA) including it can be prevented.

[0175] Although embodiments of the present invention have been described above with reference to the attached drawings, the present invention may be implemented in other specific forms without altering its technical concept or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. An electrode assembly comprising a first substrate tab, a second substrate tab, and a unit cell; and A pouch outer material comprising a receiving portion for accommodating the above electrode assembly, wherein The above unit cell includes an anode layer electrically connected to the first substrate tab, a cathode layer electrically connected to the second substrate tab, and a solid electrolyte layer between the anode layer and the cathode layer. The above-mentioned receiving portion includes a bottom surface on which the electrode assembly is seated, and first, second, third, and fourth sides surrounding the bottom surface, and At least one portion of the second side is adjacent to the second material tab, and The first curved surface formed where the bottom surface and the first side surface meet has a first radius of curvature, The second curved surface formed where the bottom surface and the second side surface meet has a second radius of curvature, and A solid-state battery in which the second radius of curvature is larger than the first radius of curvature.

2. In Paragraph 1, Each of the first side and the second side extends in a first direction, and A solid-state battery in which the first side and the second side are spaced apart from each other in a second direction intersecting the first direction.

3. In Paragraph 2, The first and second substrate tabs are formed in different directions, and The above-mentioned first substrate tab is an all-solid-state battery adjacent to at least one part of the above-mentioned first side.

4. In Paragraph 3, The above first and second substrate tabs are aligned with each other along the second direction, in an all-solid-state battery.

5. In Paragraph 3, The first radius of curvature is 0.1 mm to 0.6 mm, and An all-solid-state battery in which the second radius of curvature is 0.2 mm to 1.2 mm.

6. In Paragraph 2, The first and second substrate tabs are formed in the same direction, and The above first and second recording tabs are all adjacent to the above second side, all-solid-state battery.

7. In Paragraph 6, The second curved surface portion of the second side above includes a first buffered curved surface portion and a second buffered curved surface portion having different radii of curvature, and The first material tab is adjacent to the first buffer curved surface, and The above second substrate tab is an all-solid-state battery adjacent to the above second buffer curved surface.

8. In Paragraph 7, A solid-state battery in which the radius of curvature of the second buffer curved surface is larger than the radius of curvature of the first buffer curved surface.

9. In Paragraph 8, The radius of curvature of the first buffer curved surface is 0.1 mm to 0.6 mm, and An all-solid-state battery in which the radius of curvature of the second buffer curved surface is 0.2 mm to 1.2 mm.

10. In Paragraph 2, Each of the above third side and the above fourth side extends in the above second direction, and The third side and the fourth side are spaced apart from each other in the first direction, A solid-state battery in which the length of the first side in the first direction is smaller than the length of the second direction of each of the third side and the fourth side.

11. In Paragraph 1, All-solid-state battery in which the bending stiffness of the second substrate tab is greater than the bending stiffness of the first substrate tab.

12. In Paragraph 11, The above-mentioned first substrate tab includes a plurality of positive tabs, and The above-mentioned second substrate tab comprises a plurality of negative electrode tabs, in an all-solid-state battery.

13. In Paragraph 12, A solid-state battery in which the number of negative electrode tabs of the second substrate tab is greater than the number of positive electrode tabs of the first substrate tab.

14. An electrode assembly comprising a first substrate tab and a second substrate tab, wherein the bending stiffness of the second substrate tab is greater than the bending stiffness of the first substrate tab; and A pouch outer material comprising a receiving portion for accommodating the above electrode assembly, wherein The above-mentioned receiving portion includes a bottom surface on which the electrode assembly is seated, and a side wall surrounding the bottom surface. The above side wall includes a first buffer area adjacent to the first substrate tab and a second buffer area adjacent to the second substrate tab, and The first cushioning curved surface formed where the first cushioning region and the bottom surface meet has a first cushioning radius of curvature, The second cushioning curved surface formed where the second cushioning region and the bottom surface meet has a second cushioning radius of curvature, A solid-state battery in which the second buffer radius of curvature is larger than the first buffer radius of curvature.

15. In Paragraph 14, The above side wall further includes a non-buffering area which is an area other than the first buffering area and the second buffering area, and The non-buffering curved surface formed where the above non-buffering region and the above bottom surface meet has a non-buffering radius of curvature, A solid-state battery in which the first buffer radius of curvature is larger than the non-buffer radius of curvature.

16. In Paragraph 14, The above-mentioned first and second substrate tabs are formed in the same direction, for an all-solid-state battery.

17. In Paragraph 14, The first and second substrate tabs are formed in different directions, and The above first and second substrate tabs are aligned with each other along the second direction, forming an all-solid-state battery.

18. In Paragraph 14, The above-mentioned first substrate tab includes a plurality of positive tabs, and The above second substrate tab includes a plurality of cathode tabs, and A solid-state battery in which the number of negative electrode tabs of the second substrate tab is greater than the number of positive electrode tabs of the first substrate tab.

19. A bottom surface on which an electrode assembly is seated and first, second, third, and fourth sides surrounding the bottom surface, and Each of the first side and the second side extends in a first direction, and The first side and the second side are spaced apart from each other in a second direction that intersects the first direction, and The first curved surface formed by the meeting of the bottom surface and the first side surface has a first radius of curvature, The second curved surface formed by the meeting of the bottom surface and the second side surface has a second radius of curvature, and A pouch outer material for an all-solid-state battery, wherein the second radius of curvature is larger than the first radius of curvature.

20. In Paragraph 17, Each of the above third side and the above fourth side extends in the above second direction, and The third side and the fourth side are spaced apart from each other in the first direction, A pouch outer material for an all-solid-state battery, wherein the length of the first side in the first direction is smaller than the length of the second direction of each of the third side and the fourth side.

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